Analysis of Epichlorohydrin in Water using HS- GC/MS

Significance of the Topic

Epichlorohydrin is widely used in resin and glycerin production and poses health risks including respiratory and renal damage and potential carcinogenicity. Monitoring its levels in water is critical for environmental safety and regulatory compliance, especially given stringent discharge limits established by water pollution standards.

Objectives and Overview of the Study

The study aims to develop a streamlined headspace GC/MS method for quantifying epichlorohydrin in water samples. This approach seeks to meet official test criteria while reducing solvent use and preparation time compared to traditional solvent extraction methods.

Materials, Methodology and Instrumentation

A calibration series of epichlorohydrin (0.5 to 10 ug/L) with a constant internal standard level was prepared in 20 mL headspace vials. Water samples were spiked and directly analyzed without solvent extraction.
Used Instrumentation

• Headspace sampler HS-20 NX with loop injection
• Gas chromatograph Nexis GC-2030
• Mass spectrometer QP2020 NX operated in SIM mode
• Analytical column SH-624 (60 m x 0.25 mm, 1.4 um film)
• Carrier gas helium at 1.0 mL per minute

Main Results and Discussion

• Linearity: Calibration curve exhibited R2 greater than 0.999 over the concentration range of 0.5 to 10 ug/L.
• Method Detection Limit (MDL): Determined as 0.1 ug/L based on seven replicate analyses at 2.5 ug/L.
• Limit of Quantitation (LOQ): Calculated as 0.4 ug/L following standard deviation multipliers.
• Accuracy and Precision: Recovery of 90 percent with a relative standard deviation of 2.4 percent at 5 ug/L level.

Benefits and Practical Applications of the Method

The headspace GC/MS procedure simplifies sample handling by eliminating liquid extraction steps, reduces solvent consumption, and accelerates throughput. It enables routine water quality monitoring laboratories to reliably detect epichlorohydrin at levels below regulatory limits.

Future Trends and Potential Applications

Advances may include automation of vial preparation and integration with online sampling systems. The method could be extended to other volatile organic contaminants and adapted to field-deployable GC/MS platforms for real-time monitoring.

Conclusion

The validated headspace GC/MS method using HS-20 NX and QP2020 NX achieves rapid, accurate, and sensitive determination of epichlorohydrin in water, aligning with official standards while reducing solvent use and preparation time.

Reference

1. Hazards Assessment and Workplace Management of Epichlorohydrin, J Korean Soc Occup Environ Hyg, 2012, 22(2): 164-173
2. Official test method of water pollution in Korea, Epichlorohydrin-Solvent Extraction/Gas Chromatography-Mass Spectrometry ES 04608.1